The invention discloses preparation methods for fluorine-containing alpha-calcium sulfate hemihydrate powder and a fluorine-containing calcium sulfate artificial bone material, and belongs to the field of medical biological materials. The preparation method for the fluorine-containing alpha-calcium sulfate hemihydrate powder is as follows: adding a fluorinating agent in a process of adding calcium sulfate dihydrate into mixed reaction liquor of calcium chloride aqueous liquor and absolute ethyl alcohol for partly removing crystalline water to prepare alpha-calcium sulfate hemihydrate, so that fluoride ions partly substitute ions in calcium sulfate hemihydrate to prepare the fluorine-containing alpha-calcium sulfate hemihydrate powder. The fluoride ions change crystal structure of calcium sulfate hemihydrate, so that the crystalline grain feature of the fluorine-containing alpha-calcium sulfate hemihydrate powder is obviously changed to an equiaxial hexagonal prism shape from a slender prism shape. The material has good degradation property and biocompatibility, and therefore, the prepared fluorine-containing alpha-calcium sulfate hemihydrate artificial bone material can be applied to the medical repair field, for example, can be used as dental materials such as a dental cementation material, dental filler, a pit and fissure sealant, and the like, and can be used as a root canal product, and the like.